Electric rivet furnace



Oct. 13, 1925 am M a C Ffm P; L A N Aug. 3, N23- ELECTRIC RIVET FUHNACBWITNESSES:

INVENTOR ATTORNEY m m Af O 2 2 .FM a 2 2 5, m 3 1.. w 1 2 S 32N 3 *Y l ru 2 7 m 2, O m m 3 A M m Wl .IIlw \\\1 Mm m w 1 2 l A M 5, l B w w ,y2l, a R u M m M w ma M. m m 5 l m E 6 ll|\l x A u um@ w fr 1L :.0 n 1 m3. 1l M M WITNESSES: am@ af/Pn ATTORNEY Patented Oct. 13, 1925.

UNITED STATES PATENT OFFICE.

.AL-LIS I. IAUFARLAND, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR T0WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OFPENNSYL- VANIA.

ELECTRIC RIVET FURNACE.

Application led August 3, 1921.

To all whom t may concern.:

Be it known that I, ALLis M. hLxcFnn' LAND, a citizen of the Unite-dStates, and a resident of Wilkinsburg, in the county ot' Allegheny andState of Pennsylvania, have invented a new and useful Improvement inElectric Rivet Furnaces, of which thc following is a specification.

My invention relates to electric furnaces and particularly toelectrically heated rivet furnaces, and it has for its object to providea relatively simple and easily operated turnace adapted to heatsimultaneously a relatively large number of rivets.

In practising my invention, I provide a metallic drum or casing insideof which is located a plurality of ilat carbonaceous plates operativelyengaging each other over only a portion of their surfaces. Thecarbonaceous plates may be integral and substantially circular incontour, and be provided with a substantially radial slot or openingconstituting a furnace 'chamber within which the rivets are locatedWhile being heated, or the carbonaceous plates may be divided and soshaped and located relatively to each other as to form a furnace chamberwithin which the rivets may be located while being heated. Resilientmeans is provided to compress the carbonaceons plates, and suitablecontact terminals are provided to ermit of conducting the rurrent to androm the resistor.

In the drawings,

Figure 1 is a View, partl in side elevation and partly in longitucinalsection, of an electric rivet-heating furnace embodying my invention;

Fig. 2 is a view, in vertical lateral section, on the line II-II of Fig.1;

Fi 3 is a view, in side elevation oi a. modi ed form of the deviceembodying my invention, certain portions being cut away, and

Fig. 4 is a View, in vertical lateral section, of the furnaceillustrated in Fig. B, the section being taken on the line IV-IVthereof.

A furnace 5 comprises a cylindrical metallic drum or casing 6, radiallextending integral flanges 7 being rovi ed againm which heads 8 and 9may bolted. luitm able supporting members 10 are provided Serial No.489,428.

and secured to the casing 6 in any desired manner.

A lining ll of refractory insulating material is placed inside ot. thecasing l. A plurality oil relatively thin carbonzueousI plates 1Q,substantially circular in contour, are placed inside ol the re tractorylining` l1 adjacent to each other. Each ot' the plates 12 is providedwith a substantially radial opening or slot 13, an elongated furnacechamber 1K3 being formed by the plurality ot slots. Each ot the plates12 has a thickened portion 14 immediately adjacent to the slot 13 sothat the adjacent plates will operatively engage each other over only arelatively small area immediately adjacent to the chamber 13a. Anopening 15 is provided in the casing 6 which registers with the openside of the chamber 13a, and a suitable hinged door 16 may be providedto close the opening 15 when the furnace is not in use or is beingheated.

A plurality of carbonaceous blocks 1T and 18 and a metallic terminalplate 19 are provided at each end of the assembled group oi'plates 1Q.Currenteconducting leads Q() are suitably secured to the terminal plates19 and extend outwardly through insulatingl bushings 21 in the heads 8and 9.

The head El has an integral hollow evtension 22, in which is located acompres'. sion spring 23 and an adjusting screw 2l which permits oi'ladjusting the pressure upon the removable resistor plates l2.

lVhile the temperature al which the resister plates are operated to heatri vets which may be placed in the chamber l?) is not high enough tocause destructive oxida tion by the surrounding air, there is,nevertheless, some oxidation and provision may be made for counteractingsuch action. il. container Q5 is located above the casing ll in whichmay be placed any suitable hydrocarbonaceons oil which is permitted ltodrip through a tube 26 upon the heated resistor' plates and becomevolatilized thereby. The sooty vapor produced by this action iseltective to neutralize the oxidizing effect of the air by substantiallypreventino its coming in contact with the plates. A device to pr ducesuch lsooty vapors is described and claimed in a copending application,Serial No. 454,776, tiled March 23, 1921, by Gr. M,

Little and vassigned to the Westinghouse Electric & Mfg. Company.

In the modlfication illustrated in Figs. 3 and 4, a casino' 27,illustrated as substantially rectangular in lateral section, is providedWith suitable supporting members 10. Heads 8 and 9 are bolited to theflanged portions 7 at the respective ends of the casplurality ofrefractory bricks or blocks 28 and 29 are located inside of the casingQ7 in side-by-side relation to provide a chamber in which may be locateda plurality of carbonaceous resistor plates 30 and 31j The plates 31.are located between the parallel extending plates 3() and constitute theback wall otl the furnace chamber. Intermediate plates 32, substantiallycoextensivc horizontallyvivith the plates 30, may be provided to form aplurality of small heating chambers 13. The thickness of the plates 30and 31 is greater over a small portion of the cross section of theplates immediately adjacent the chamber 13 so that the adjacent platesengage each other over only a small portion of their total area. Thisreduces the area traversed by the current, whereby the resistance of thecurrent path is increased.

Means for compressing the resistor may comprise substantially the sameelements as those described in connection with the device illustrated inFigs. 1 and 2. Similar cui rent-conducting means are also provided.

It may be noted that the device embodying my invention provides arelatively simple, easily assembled and easily maintained furnace forheating a plurality of rivets, the resistor of which is formed of aplural ity ot' carl'ionaceous plates, portions only of the surfaces ofthe adjacent plates being in operative engagement with cach other.

Various modifications may be made in the device embodying my inventionwithout departing Vl'rom the spirit and scope thcrcol' and I desire thatonly such limitations shall be placed thereon as are imposed by thelprior art or are specifically set forth in the. appended claims.

l claim as my invention:

l. An electric furnace comprising a plurality of relatively thinrefractory resistor members having substantially radial slots therein toform a furnace chamber.

2. An electric furnace comprising a plurality of relatively thinrefractory resistor members having substantially radial slots therein toform a furnace chamber, the adjacent resistor members operativelengaging each other adjacent to said radia slots only.

3. An electric furnace comprising a lurality of relatively thincarbonaceous p as placed in side-by-side relation, and havingsubstantially radially extending slots to form a furnace chamber, theadjacent plates having operative engagement with each other over only anarrow portion adjacent said slots, and means for permitting a curieutto traverse the engaging portions of the plates.

4. An electric furnace comprising a casing, a plurality of relativelythin carbonaceous plates located in side-by-side relation and havingsubstantiall radial slots therein to form a furnace cham r and theadjacent plates operatively engaging each other over a narrow stripportion adjacent said slots, means for conducting current to and from.said plurality of plates, and heat-insulating material located betweensaid casing and said plurality of plates.

5. An electric furnace comprising a casing, a furnace chamber formed bya plurality of relatively thin carbonaceous plates provided with slotsand having their fiat sides operatively engaging each other over anarrow strip portion adjacent to the chamber formed by said slots, meansfor conducting current to and from said plates, means ior resilientlycompressing said plates, and heat-insulating material located betweensaid casing and said plates.

6. An electric furnace comprising a heatinsulating casing. a pluralityof relatively thin carbonaceous plates located in said Casing and soshaped aml disposed as to provide a l'nrnace chamber extendingtransversely of .said casing, the lint sides of adjacent platesoperatively engaging each other over a nar rou' strip portion adjacentto the chamber, resilient compressingr means for said plates and meansfor conductingr current to and from said plates.

ln testimony whereof, l have hereunto subscribed my name this 28th dayof July 192i.

ALLIS M'. MAcFAltLANl).

